A stent is a small tube used in medical procedures to help keep structures such as blood vessels and arteries open. Stents can also be used to keep other body ducts open. Stents are often used after angioplasty, which is a procedure that uses a small balloon-like structure to open partially closed heart arteries. The stent is then placed in the artery to help keep the artery open. There are three main types of stents: stent grafts, bare-metal stents and drug-eluting stents.
Stent Graft
While most stents are made of plastic or metal, a stent graft is composed of fabric. Its shape is supported by a metal mesh. It can be used for different purposes, but it is used mainly to treat aneurysms, which are weak spots in arteries. The weak spots can balloon and burst, causing fatal internal bleeding. Stent grafts are designed to seal tightly with the artery beyond both ends of the artery's weak spot and allow blood to flow safely through.
Bare-metal Stents
Bare-metal stents are simple metal tubes that can be made from stainless steel or nickel-titanium alloy. They are used to keep blood vessels open after blockage. They are used after a balloon-tipped catheter is fed into the blood vessel to the point of blockage. The balloon is inflated, opening the vessel. A bare metal stent is inserted to keep the vessel open.
Drug-eluting Stent
A drug-eluting stent is similar to a bare-metal stent, except that it is coated with a drug that helps to fight stenosis, which is a blockage of the blood vessel. Stenosis is caused by the proliferation of cells, and the drug helps to prevent the proliferation. The procedure for insertion of a drug-eluting stent is the same as for a bare-metal stent.
